Walter f



(No Model.)

W. F. SMITH.

INGANDBSCENT LAMP SOCKET AND KEY.

No. 435,047. Patented Aug. 26, 1890.

Wmo/am". y @MAW/mm:

UNITEDy STA-TES .PATENT OEEICE.

WALTER E. SMITI-I, OE PHILADELPHIA, PENNSYLVANIA, ASSIGNOR To THE v UNITED ELECTRIC IMPROVEMENT COMPANY, OE GLOUCESTER CITY,

NEIV JERSEY.

lNCANDESCENT-LAMP SOCKET AND KEY.

v,SPECIFICATION forming part of Letters Patent No. 435,047, dated August 26, 1890.

'Application filed August 23,1889. Serial No.'32l,723 (No model.) l

To all whom it may concern.-

Be it known that I, WALTERV F. SMITH, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and Stateof Pennsylvania, have invented certain new and useful Improvements in Gut-Out Devices for Incandescent Electric Lamps, of which the following is a specification.

The principal object of my invention is to 1o provide a cut-out device for electric lamps of Simple construction, positive in action, and capable of being readily adjusted.

My invention consists of a cut-out device constructed, arranged, and operating in the manner hereinafter particularly described,

and pointed out in the claim. v l

The nature and characteristic features of my invention will be Inore fully understood taken in connection With the 'accompanying 2o drawings, forming part hereof, andin Which- Figure l is a view partly in elevation and partly in Section of an electric-lamp holder or socket with my improved cut-out device applied thereto. Fig. 2 is a similar view of 2 5 myimproved automatic cut-out device, show ing portions of au incandescent electric lamp, shunt-circuit, the tube or rod interposed in said circuit, and the means for Short-circuiting the dynamo or generator current through 3o the electric lamp. l

Referring now to the drawings, is a circular base-plate of insulating material, as hard rubber, having au annular aperture x formed therein. The vertical metal support A, Secured to thebase-plate m, is bifurcated at a4 and provided with a bearing a5 and a binding-screw or other terminal device a3. The vertical metal support A secured to the base-plate is provided near its upper ex- 4o tremity With a binding-screw .or other terminal device a7 and with a circular aperture a.

The filament y is secured to the vertical supports A and A in any preferred manner.

E is a lever, provided at one extremity thereof with a finger e, and this lever is pivotally connected to the bifurcated suplport at. A spring F, interposed between the vlever E and the upper extremity of the support A, is in compression and' tends to force the finger e of the lever E into close contact 5o With the vertical support A'. 5

Cisa circular metal plug adapted to fit into the orifice a6 of the support A. This metal plug C is provided with' a tapped chamber c to receive the rod or tube Gr. Onto 5 5 the threaded-shank ofthe plug C is mounted or secured an insulating thumb-piece D.

Gis a circular tube Or rod of high electrical resistance and substantial strength, yet capable of being melted or softened at a low tem- 6o perature, and provided with a metallic ferrule D at one end thereof., This rod or tube is secured into the chamber c of the metallic plug C. In practice good resultshave been obtainedvby making this tube or rod .G of rubber .and graphite; but it may be made of any y other preferred insulating material.

K and K are the two wires or other conductors attached to the terminals d'3 and a7, respectively, leading from the source lof elec- 7o trical energy.

I is a threaded thimble secured to the baseplate by which the lamp socket or holder is secured to the electrolier or other fixture. The wires K and K pass through the aper- 75 ture x in the base-plate andv through the thimble I.

f I is `the housing of the vlamp socket or holder, insulated from the thimble I by means of a gasket w. 8o

I2 is a Supportfor the globe or shade I3, which is illustrated in dotted or broken lines in Fig. l.

Itis the glass bulb or vacuum-chamber of any preferred construction.

:v2 and :r3 are insulating-disks supporting the vertical conductors A and A and the housing I. f

M.and M are spring-actuated clamps, of the usual or any preferred construction, and 9o which serve to retain the glass bulborvacuumchamber in position.

N is asvvitch adapted to short-circuit the filament y, and thereby extinguish the lamp.

The mode of operation of my improved cutout device is as follows: To adjust the cutout device the plug C, carrying the rod or tube Gr, is first introduced. through theopeningin the vertical arm A with the ferrule D in Contact with the arm of the lever E until the resistance of the spring F is overv come, when the finger e is raised and the contact between the said finger and the vertical support A is broken. The lamp is then interposed in the dynamo or generator circuit.

supports A and A and the lilament y to the source of electric energy at the same time the shunt current traverses the ferrule D and the tube or rod G to the source of the electric energy. If the filament y is broken or otherwise injured, the intensity of the shunt-circuit will be greatly increased, and the tube or rod G will, by reason of its high electrical resistance, become melted or softened, so that the spring F will cause it to yield or bend and force the fingere into Contact with the vertical support A, whereby the electric current is short-circuited through the lever E and the lamp cut out of the dynamo or generator circuit. When the broken or otherwise injured ilamcnt has been replaced by a new one, and when the rod or tube G has become cool or hard, the cut-out device maybe readjusted so as to include the lamp in the dynamo or generator circuit by simply rotating the plug C, the tube or rod G, and ferrule D" by means of the thumb-piece D. The rotation of the plug C by reason of the bent form of the tube or rod G forces the ferrule D into contact with the lever E to overcome the resistance of the spring F and to raise the finger e, thereby opening the shuntcircuit and including the lamp again in the dynamo or generator circuit. The dynamo or generator current may be short-circuited and the lamp excluded therefrom, either by revolving or withdrawing the plug C; but in either case the spring F will force the iinger e into contact with the vertical support A and thereby close the shunt-circuit, as will be readily understood.

Having thus described the nature and objects of my invention,what Iclaim as new, and desire to secure by Letters Patent, is-a The combination, in an electric lamp, of two vertical supports, a short-circuiting lever pivotally connected with one ot said sup ports, a spring interposed between said lever and support, a metal plug provided with a threaded shank mounted in the other of said supports, an insulated thumb-piece mounted thereon, a tube or rod melting or softening at a low temperature mounted in said plug, and a metallic ferrule secured to the opposite end of said tube or rod, all arranged in the manner and for the purposes described.

In witness whereof I have hereunto set m y signature in the presence of two subscribing witnesses. f WVALTER F. SMITH. Witnesses:

ALEX. C. I-IUMPHREYS, CHARLES E. SMALL. 

